1. Field of the Invention
Embodiments of the invention relate to the field of enterprise storage systems. In particular, embodiments of the invention further relate to proactive detection of data inconsistencies in a storage system point-in-time copy of data.
2. Background of the Invention
Business critical enterprise applications suffer data loss or downtime from data failure events. Events such as logical or physical data corruption, failures of the storage controllers, disks, and other Storage Area Network (SAN) components, or a complete site failure may cause data loss or downtime. Data corruption is one of the most common causes of data loss and may be caused when a value of a data's variables are incorrect, deleted, or unreadable. Data corruption may be caused by human configuration errors, physical media or firmware errors, logical software bugs, and virus attacks or malicious worms. The physical media errors may be caused by hardware problems associated with storage, caching, controller firmware bugs, or multi-path drivers.
A point-in-time copy of data is a copy of the state of a storage device at a give point-in-time. Point-in-time copies of data are used to restore data stored on the storage device. The original copy of the data continues to be the primary copy of data, available without interruption, while the point-in-time copy is used to perform other functions. A point-in-time copy of a data volume may be a logical copy of the data volume where only the changed data blocks are maintained, also referred to as a snapshot. A point-in-time copy of a data volume can also be a physical copy of the data volume where a complete copy of the data volume is created on a different set of physical disks, also referred to as a clone.
Point-in-time copies of data are typically used in conjunction with high-availability systems to enable application availability and efficient system and data recovery. A point-in-time copy of data may be used to revert back to data at a previous satisfactory state to resolve a data error in the primary copy of data. System administrators manually restore the most recent point-in-time copies of data until a consistent point-in-time copy of data is restored without data integrity errors.